Change speed gear



June 29,1943. G. MEYER; 2,323,070

CHANGE SPEED GEAR Filed Feb. 4, 1941 l I aa m E "5 a 2 a '3 N I a '0 Q m:3 Y N v mg THU IHHHH I w 3'; S m

Q 1 1 i x\ Jnvenfor:

G am" Meyer A tho-r7 5 Patented June 29, 1943 CHANGE SPEED GEAR GustavMeyer, Frledrichshafen-on-the-Bodensee,

Germany; dian vested in the Allen Property Custo- Application February4, 1941, Serial No. 377,363

r In Germany February 2, 1940 6 Claims. (01; 74-339) My inventionrelates to change speed gears especially in motor vehicles and hasspecial ref erence to gears of this kind which are provided withso-called overrunning couplings, for example clutches having claws withsoinclined front faces that when getting into touch the coupling halvesare at first repulsed until the originally slower half is so speeded upor the originally faster half is so slowed down that the movement ofrotation of the two halves in relation to each other is reversed,whereupon engagement takes place.

-In change speed gears of thiskind it is difficult to change intocertain speeds when the vehicle is at rest, as certain coupling halvesin connection with the motor side have to be slowed down so as to runslower than their respective other 7 halves in connection with the carside in order to be engaged, and since the latter halves are standingstill, overrunning in the desired direction is impossible.

According to my invention I avoid these difliculties by providing aspecial kind of braking device or clutch, for example a, friction clutchor the like, having a member in rotating connection with rotatingelements in the change speed gear and another member in direct rotatingconnection with the driving motor, and means for reversing one of saidmembers as compared with the normal driving direction. For this purpose,according to my'invention, I prefer to provide areversing device drivenby the incoming or motor shaft of the change speed gear and driving afirst clutch element journaied for instance on the lay shaft or on anextension thereof and adapted to co-operate with a second clutch elementwhich is in driving connection with one of the rotating members of thechange speed gear which has to be reduced in speed for causing thedesired engagement with a member standing still. As it is necessary toreduce the speed of rotation to such an extent that the member at restoverruns the other member this demand can onlybe fulfilled by reversingthe direction of rotation of the rotating member so that,.seen in theoriginal turning direction, the member standing still now in effectrotates relatively faster than the other member rotating backwards. Thusit is akind of braking which is performed by means of a braking elementwhich instead of being fixed as is normally the case with one of thebraking elements of prior types of brakes rotates in the directionreverse to the direction of rotation of theelement to be braked.

Therefore, in such cases in which a braking device for braking thefaster running coupling half is provided anyhow, nothing else isnecessary but means for rotating the normally fixed part of the brake inthe direction reverse to the normal direction of rotation of therotating part thereof.

The auxiliary friction or braking device need not be situated on the layshaft, as will easily be seen when explaining the drawing, butI preferto provide it there as this has the advantage. of giving a comparativelysimple construction.

Of course, the operation of the braking or friction device maybemadedepending on the course of the speed change, as explained in'the U. S.

Patent 2,086,723.

My invention is of special importance and advantage with heavy cars andvehicles which have to overcome great resistances. With vehicles of thiskind after having started in a lower speed it is often not possiblebecause of great resistances to perfect a change to a higher speed,because the car would come to a stop, whereas it wouldbe possible todrive the car with such higher speed transmission after this was onceset. Thus it is a great improvement with my invention to be able to setsuch higher speed transmission while the car stops and to start withfull motor power.

Having given a general description of my invention I now want to pointit out more in detail having reference to the drawing wh an exampleembodying my invention.

The figure is a diagrammatical longitudinal section through the casingof a change speed gear showing the gears and clutches in side view butthe new braking device mostly in section.

. The left hand side is assumed to be the motor side of the change speedgear and shaft 1 is the outgoing shaft of the motor. pairs of.constantly'meshing gear pairs l/2, 3/4, 5/ 6. The main clutch '8 can beoperated by means of sleeve ll, splined at I! to the incoming shaft B ofthe speed gear, adapted to be shifted by levers 9 and ID. The shaftportions of the main shaft train are journaled at H, [5, l6, l1 and H.The out-going shaft is designated by the numeral '20; its direction ofrotation is indicated by the arrow; shaft portions l9 and 29 havingtheir 5 opposing ends journaled inside of gear 3 (the ich representsThere are three I as follows:

co-operate with claw coupling half 33 on the left hand side of gear 4.

Another shiftable sleeve 31 is splined to mai shaft portion 23: its lefthand side and the right hand side of gear 3 both are shaped to form. twoco-operating claw couplingihalves '33 and 38, respectively. A similarsleeve ll is splined to lay shaft portion 21, and its left hand sidetogether with the right hand side of gear: 3 form a claw couplingcomprising coupling halves 42 and 43. v

By means of double-armed lever Ii sleeves 3i and 34 are made to operatealternately; and

similarly double-armed lever I2 causes alternate operation of sleeves 31and II.

Shaft portion 43 is a continuation 'of shaft portion 28. and isiournaled at M and at M.

The change speed gear and the main clutch are surrounded by a casing 30.

With the change speed gear represented it is possible to get four speedsin which the different elements are forming part of the transmissionpast coupling half 33 without getting into en- -gagement,vtheir clawsrepuising each other.

For the purpose of coming to the desired engagement, main clutch 8 beingdisconnected, friction cones 54 and 55 are brought into engagement byallowing fluid pressure to enter into cylinder Si by means of a controldevice (not 1st speed-Incoming shaft l3, gear I, gear 2,

shaft portion 23, coupling 35/38, gear 4, gear 3. coupling 33/33, shaftportion 29, out-going shaft 4 2nd speed-Incoming shaft l3, gear I, gear2,

' shaft portion 23, coupling 33/33, coupling 43/32,

shaft portion 21, gear 3, gear 5, outgoing shaft 23;

3rd speed (direct speed) .-Incoming shaft i3,

shaft portion i3, coupling 32/33, coupling 33/33, shaft portion 28,outgoing shaft 23;

7 4th speed (overspeed). --Incomlng shaft i3, shaft portion l3, coupling32/33, .gear 3, gear 4.

coupling 43/42, shaft portion 2], gear 3, gear 5,

out-going shaft 23;

v vThe long arrows in dotted lines indicate the direction of rotation ofthe different gears.

splined to shaft 43 and adapted to be shifted. into and out of operationby means of lever 53, piston rod 53 and piston 33 sliding inside ofcylinder 6|. This piston may be moved by fluid pressure for instance,fed through conduit 62 and acting against the pressure of spring 33. p

The operation of the device isas follows:

Assuming the vehicle to which the motor M and the change speed gearbelong be at rest and the speed gear be set to the first speed, asindicated in the drawing, and it be desired to change to the third speedand to start therewith. For this purpose it is necessary to disengagecoupling 38/33 and to cause engagement of coupling 32/33.

The inclination of the front faces of the claws of coupling 32/33 is sochosenthat, when the gearsare rotating and coupling 33/33 isdisconnected the claws of coupling 32/33 getting into contact, theseclaws repulse each other (coupling half 32 running faster than couplinghalf 33) until coupling half 32 was so reduced in speed of rotation thatcoupling half 33 begins to over run 32, in which moment the claws cometo final engagement.

Now, if the vehicle is at rest both coupling halves 32 and 33 arestanding still, and if new the motor is started coupling half will runrepresented). Consequently, shaft extension 43 and with it shaft portion26 and gear 2 are rotated in' the direction reverse to the normaldirection of rotation, because of the reversing gear 52. This reversedirection of gear 2 is also transmitted to gear I, shaft portion i3 andsleeve 3|; it is indicated in the drawing by small ar-,

rows. Coupling half 32 beginning to rotate in this reverse direction andat the same time being pressed against coupling half 33 immediatelygets. into engagement therewith so that coupling 32/33 is connected.Then braking device or friction clutch 54/55 is disengaged and mainclutch 3 is engaged by the driver. Now the vehicle may start in thedesired speed.

I do not want to be limited to the details described or shown in thedrawing as many variations will occur to those skilled in the artwithout'deviating from the scope of my invention.

What I claim is: 1 1. In a change speed gear with constantly meshinggear pairs and couplings adapted to get into engagement after one halfof one of said couplings has overrun its other half, an auxiliaryfriction device, said device comprising a first member adapted to berotated independently of the change speed gear by the main drivingengine, a second member adapted to rotate with one of the rotatingelements of said change speed gear, means for causing one of saidmembers to rotate in the direction reverse to the normal direction ofrotation of said other member, and

normal direction.

2. An auxiliary braking device for a change speed gear having constantlymeshing gear pairs and coupling means selectively operative to effect adrive through different gear pairs, said device including a gear fixedto the outgoing shaft of the engine transmitting to the change speedgear, a gear loosely journaled on an extension of the lay shaft of thechange speed gear, a third gear inserted between said two mentionedgears and being in constant mesh therewith, a sleeve splined to said layshaft extension, a friction surface on said third gear and a frictionsurface on said sleeve, said friction surfaces being adapted to engagewith each other, and means for shifting said two friction surfaces intoand out of engagement.

3. In a change speed gear with constantly meshing gear pairs andcouplings adapted to get into engagement after one half of one of saidcouplings has overrun its other half, a braking device for braking thespeed of rotation of one half of a coupling comprising a'firstbraking'element rotatable with'said coupling half and a ment of saidbraking device to rotate reversely to the normal direction of rotationof the first braking element whereby, when said braking elements areengaged, the coupling halt with which of the power input shaft of themain shaft train to rotate at least certain of the gears on the layshaft train in a direction reverse to their normal direction ofrotation.

5. In achange speed gear having a main shaft train and a lay shaft trainincluding constantlymeshing gear pairs and coacting coupling halves forselectively eifecting a driving connection.

halves, said device including means driven independently of the mainclutch and operative through the lay shaft train to effect reverserotation of a coupling half when said coupling half is running fasterthan its coacting coupling half,

and means for rendering said reversing means operative and inoperative.

6. In a change speed gear with constantly meshing gear pairs andcouplings adapted to get into engagement after one half of said couplinghas overrun its other half, an engine haft, a

' clutchthrough which the engine shaft drives the through the diflerentgear pairs, a main clutch e at the power input end of the main shafttrain through which the main shaft train is' adapted to be driven from adriving motor, a device for expediting engagement of coacting coupling20 and inoperative.

main shaft train of the change speed gear, an extension on the lay shafttrain of the change speed gear, gearing means betweenathe engine shaftand the lay shaft extension operative to rotate the lay shaft reverselyto its normal direction of rotation, and friction clutch means forrendering said reverse gearing means operative GUSTAV MEYER.

